In Applicants' above-referenced and incorporated co-pending applications for U.S. patent, novel apparatus and methodology are disclosed for examining and appraising the physiological or compositional state or condition of, biological (organic) material; in particular, for conducting in vivo examination and assessment of the physiological state or condition of human tissue, for example diagnostic examination of the breast (or other anatomical portion) of live human subjects.
In accordance with the above-noted referenced and incorporated methodology and apparatus, selected light spectra are introduced into the subject being examined at selected locations, and the light energy so infused is then received (e.g., detected) at other particular locations, preferably including a pair of such other locations, for example, a "near" location closer to the point of light infusion and a "far" location disposed more remote from that point. As described more fully in the referenced co-pending applications, the use of at least two such receivers and the distances between the point of initial light insertion and the points of light reception are important factors in the useful application of the resulting data (i.e., the measured values of light intensity as determined by the detectors themselves).
Thus, the "optical probe" by which the optical response data is obtained incorporates means whereby the particular distance between the two optical "heads" (i.e., the light-producing and the light-receiving instrumentalities) may be determined in any given position to which the two such heads are adjusted to accommodate the size of a particular subject of examination. Such distance determinations, which may be designated "nominal optical distances", are inputted into the computing apparatus which is used to process the data, where they are utilized with other computation processes to "condition" or convert the "raw" data from the detectors so that it becomes representative of the intrinsic internal tissue composition of the subject under examination, i.e., independent of factors such as specimen (e.g., breast) thickness and boundary effects (e.g., skin pigmentation, etc.).
Such "conditioned" data, representative of intrinsic internal physiological state or condition, is of great value in portraying and understanding the actual internal nature of the particular tissue under examination, and a particularly useful manner in which such tissue characterization may be presented and apprehended is, as disclosed in co-pending application Ser. No. 542,022 ( now U.S. Pat. No. 4,570,638) by way of graphical presentations which constitute, in effect, spectrally-based, optical "profiles" of a given patient or other subject. As noted in this patent, such profiles may be visually contrasted in different ways with other such profiles, whether representative of the same patient or subject or other patients or subjects. For example, in human breast examination, comparison may be made to other profiles taken at adjacent or related positions on the same breast, and in contralateral studies, where profiles taken at the same locations on opposite breasts of the same patient are compared to one another. Additionally, such "profiles" may very advantageously be compared with other analogous profiles taken from other patients, whereby variations and abnormalities may be noted and taken under consideration.